<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>

</body>
<script>

    // var arr = {
    //     a: 1,
    //     b: 2,
    //     c: {
    //         d: 3
    //     }
    // }
    // var arr1 = Object.assign(arr)
    // arr1.a = 3
    // console.log(arr1);
    // console.log(arr)



    // var obj = [0,1,2,3,4,5,6,7,8,9]
    // obj1 = obj
    // obj[0] = 52
    // console.log(obj);
    // console.log(obj1);



    try {
        console.log(137982);
        var aa = 555
        if (aa != 666) {
           throw '999' 
        }
        
    } catch {
        console.log(321);
    } finally {
        console.log(987);
    }

</script>

</html>